Many functional thin films are practically used in the fields of semiconductor devices, displays and luminescent elements. Functional thin films are formed by disposing a material having a desired property at a desired position, followed by patterning. The functional thin films are used as wiring, electrodes, insulating layers, luminescence layers, optical thin films, etc.
For example, a photoresist pattern obtained by photolithography may be mentioned. However, processes of the photolithography are complex, and utilization efficiency of energy, material, etc. is low. Further, there is a problem such that since the processes of the photolithography are carried out in a clean room, cost of facilities is expensive.
As a method to solve the problems of the photolithography, an ink-jet print method has been proposed. However, in the ink-jet print method, position accuracy is low, and it is difficult to form a fine pattern. Under the circumstance, the following methods (1) and (2) have been proposed to improve the position accuracy by preliminarily forming on a substrate surface a base film having a water repellent region which repels ink and a hydrophilic region which accepts ink.
(1) A method wherein a photocatalyst such as titanium oxide is activated at a time of exposure to change a wet property of a surfactant, or a photocatalyst decomposable substance is decomposed and removed, thereby to form a pattern which accepts or repels printing ink or a toner (Patent Document 1). Paten Document 1 discloses that in a silicon resin having a siloxane bond (—Si—O—) as a main skeleton to be used as a binder for a photocatalyst, an organic group bonded to a silicon atom is substituted with an oxygen-containing group by action of the photocatalyst, whereby the wet property is improved.
(2) A method wherein a surface of a substrate is subjected to a hydrophilic treatment, and then a pattern of an organic monomolecular film of a fluorinated alkylsilane is formed by chemical vapor deposition, whereby the monomolecular film becomes a resist film for etching (Patent Document 2). Patent document 2 discloses a method wherein hydrophilic treatment is carried out by irradiating a surface of a substrate such as a single crystal silicon (natural oxidation surface SiO2), a polyethylene film or glass with ultraviolet light of Xe2 excimer laser (172 nm) or oxygen plasma. Further, it is disclosed that the organic monomolecular film of a fluorinated alkylsilane is formed by applying ultraviolet light (172 nm) or electron beam.
Patent Document 1 JP-A-11-344804
Patent Document 2 JP-A-2000-282240